Only You
by Puckleberryfan82
Summary: this is a fic about Serveride OFC and Casey Hallie. I love Casey Hallie so any fics I do on this show will have Casey Hallie a big part of it but this is mostly Serveride and my OFC. This will be rated M cause I do almost all my fics with an M rating lol.
1. Chapter 1

**Hey guys this is my first Chicago Fire fic and it is based around Serveride/OC but it also is havey on the Casey/Hallie side too. I'm not sure where this fic is going and why my OC is about cause I have just started writing it with out an plans writing out with this. I will try and update this again very soon. Please make sure you R&R this fic so I know if I am wasting my time with this or not. **

Chapter 1

MaKayla "Mac" Brady was a lot of things but shy was not one of them. She saw a guy she liked then she would walk up to them and start to flirt and talk to them but that was all before her last boyfriend. He made her change and soon she was no longer like she was before. She started to stay at him more and more till soon she didn't hang out with her friends anymore or did the fun things she liked to do before Ryan came around. Soon she realized that this was not a healthy relationship and she left him. She came to Chicago to live with her best friend Hallie Thomas till she got up on her feet. I the mean time she is back in med school so she can become a surgeon she always wanted to be. She wanted to be a Neuro surgeon cause when she was in her teens she had a massive tumor on her brain and she got the most wonderful dr who even though everyone else said it couldn't be done he wouldn't listen to them and he saved her life.

"Hallie, are you sure this is alright? I don't want to put you or Casey out if it isn't." Mac told her.

"Mac, I told you that it was in fact it was Casey that said you needed to come live with us when you had finally been able to get away from Ryan." Hallie told her as she sat down on the sofa and patted it waiting for Mac to sit down next to her.

Mac took the hint and she sat down and let out a long breath. "I can't believe I am rid of him. I never thought I would be."

Hallie nods her head at that and then smiles at her. "I know honey but you are and not only are you rid of Ryan but you are back in med school finishing up your last year and soon you will be back in the hospital being the Dr you always wanted to be."

"Yes I am and I am so excited that I am back on the track to being a Dr." Mac told her as she hugged her.

"Well now that we have that out of the way what do you say we see if Casey is doing anything after his shift maybe we can go hang out at the bar that he and his fire station hangs out at after work?" Hallie asked her with soft eyes.

"Yes I think that would be fun plus I could use some new friends so I am over staying my welcome here by being here all the time." Mac told her as she laughed at the way Hallie just throw a pillow at her head.

Fire house 51 was in a crazy time having just returned from a huge fire. Matthew Casey and Kelly Severide where busy fixing up the trucks when Casey saw Hallie and Mac come walking into the house.

"Well if it isn't the two most beautiful women around. What are you guys up to?" Casey asked them as he kissed Hallie and then gave Mac a kiss on the forehead.

Mac blushes at the brotherly love he shows her. "Hallie and I were wonder what you and your co workers are up too after work cause we thought maybe a get together at your guys favorite bar."

Casey nods his head and then looks over at Severide. "What do you think Severide? You up for a night at our bar?"

Severide who has been busy starring at Mac just smiles and nods his head. "You bet Casey. So are you going to introduce me to this beautiful women or what."

Casey smirks and then shakes his head. "I guess I can introduce you guys. Kelly this is MaKayla Brady or Mac as she likes to be called. She is Hallie's friend from back home and she has just moved here to finish up her last year in Med school so she can be a Dr."

When Kelly hears that he smiles at her. "Well another dr in this bunch huh. Well I guess we have to even out the whole Fireman's around her huh?"

Mac could see how hot he was but she was still scared around guys cause of what Ryan made her believe.

"It is nice to meet you Kelly." Mac said as she gave him a shy smile. Mac then turned to Hallie. "Can we go get something to eat? I don't want to be too hungry when we are out tonight."

Hallie knowing why she wanted to leave turned to face Casey and Severide. "Yea let's go eat so we will meet you there at say 7. Is that good for you guys?"

Casey and Severide nod their heads and then after kissing Casey Hallie and Mac leave and head to get some food and kill the next couple of hours till they meet everyone at the bar.

"Was it something I said?" Kelly asked Casey with a confused look on his face at the way they left so fast.

"No it wasn't. I think Mac likes you but the last guy she was with messed her up big time so before you start chasing her and trying to get her into bed make sure she is what you really want cause if you hurt her I will have to hurt you." Casey told Severide and then he turned to let everyone else know what was up for the night.

Severide watched Casey leave and was shock at how protective Casey was of Mac but then he got to thinking about what he said and shock his head. He would hang out with her a bit to see what she was thinking and that will also give him a chance to make sure that Mac was the girl of his dreams and not just meant to be a one night stand. If Casey can be with one girl why can't he?


	2. Chapter 2

_**K guys I know this isn't as long as the last one but I hope it is still a good one and I am sorry for the long wait for this update. I will try and not keep you all waiting a long time again lol Please make sure you R&R so I know if it is any good. Ty for all the likes and the one review I have gotten so far. I am still new to this famdom do I am happy it is being well liked.**_

Chapter 2

That night all of the station house 51 was out the local bar and they were all looking for Hallie and Mac to come. They had heard that Hallie's best friend from back home was staying with Casey and her.

"That is Hallie's friend." Leslie Shay said her best girl friend Gabriela Dawson as she pointed to Hallie and a girl with dark brown hair.

"Why are they pointing at us?" Mac asked Hallie as they got to Casey and Severide.

Hallie looked at who was pointing and then got an angry look at them. Hallie without turning to look at Casey spoke to him.

"Matt can you please go tell Dawson and Shay not to point at us. It is making Mac feel very uncomfortable." Hallie told him and to take one look at Mac you could see she was ready to bolt out the door.

"Yea I got it this babe. Be right back." Casey said as he kissed Hallie and then Mac and left to head over to Shay and Dawson.

While Casey was doing what Hallie asked him to do Mac sat down on a stool on the other side of Severide while Hallie sat next to Casey at the bar. Mac had told Hallie that she was wanted to try and be a normal girl tonight so as long as Hallie was within seeing range then Mac was alright not seating with her and Casey.

When Severide saw her sit down next to him he smiled at her. "Hey you alright?"

Mac smiled at him and nods her head. "Yea sorry. New people make me nervous. My last boyfriend really took a lot out of me. He had me to the point where I didn't even have fun and leave my home so this is like high school all over again." Mac told him with a laugh.

When Kelly heard that left he just smiled. "Well if this is like high school I should let you in on a little secret. I am the huge player then."

"I have heard that about you. Well that might hurt your ego cause I don't plane on letting you take me too bed." Mac told him with a smirk.

"Ouch." Kelly said acting like he had just been shot in the chest. "That hurts. Don't you find me attractive at all?"

Mac blushes at that. "Of course I do but I will not be sleeping with anyone least of all a player till they prove to me that they are a good guy. So Kelly Severide are you a good guy?"

When Kelly heard that he smirked. "I like to think I am. I am after all a fire fighter."

"Yes you are but you could just be using that as a way to get the ladies. Tell me Severide have you ever had a real girlfriend and not just one night stands?" Mac asked him with a smirk of her own that made Kelly's insides melt.

"I did indeed have a girl once. I was going to marry her but it didn't work out." Kelly told Mac.

"I'm sorry." Mac said losing her smirk and giving Kelly a sincere smile.

"Thanks but I like to think of it this way it lead me to meeting you." Kelly said with his smirk again.

"Oh that was good. Well played. I bow down to the player." Mac said as she bowed down to him. Making both Kelly and Mac laugh.

Mean while over at Shay and Dawson's table they saw Casey coming over to them. They saw he was no happy but they didn't know what they did wrong.

"What's up Case?" Dawson asked with a smile.

"I need you guys not to be pointing and making it noticeable that you are talking about Mac. She just got out of a very bad relationship and is just starting to get her feet wet again with people and you two are making her uncomfortable. I know you guys didn't know but now you do so please just watch what you say and do." Casey said and then he walked back over to Hallie at the bar.

When Casey got over to Hallie he found her watching and smiling at Mac and Severide. When he looked at them he smiled too cause Mac was having fun and laughing and that isn't something she has done in a long time.

"I think she will be alright Casey." Hallie said as she moved into his arms.

"I do too Hallie and just think maybe just maybe playboy Kelly Severide has finally found his match and is ready to settle down." Casey said as he hugged her close to him and they both smiled at the happy look Mac had.


	3. Chapter 3

_**hey guys sorry for the long wait on this update. I know it isn't long but at least it is an update and I will try and not make you wait to long for the next one :)**_

Chapter 3

Last night had been a fun time for Severide and he was really happy that he wasn't just thinking of her as a one night stand. He was thinking maybe just maybe he could have a happy life with one girl again. After what his ex did to him he never thought he would want to do the whole relationship thing again but MaKayla is slowly making him think twice on that decision.

After he got to work today Casey was out side waiting for him. When Severide saw him he was sure he was in for a lecture so he braced himself but what he found was what shocked him.

"Casey, what's up?" Kelly asked him with a confused look on his face.

Casey saw the look Kelly gave him at first but now he saw he looked confused. "I wanted to talk to you before we go in there and everyone hears this. I am only telling you cause Mac wants me too and she is still scared to talk about it."

When Kelly heard this he was on full alert and wondering what could have Mac so scared to talk to him about it. He thought they had a great night last night at the bar. Kelly was about to ask that when Casey beat him to it.

"Look before you start to second guess what you were feeling last night let me tell you that his has nothing to do with you and everything to do with her last relationship. Look his name was Ryan and he was the first real boyfriend Mac had ever had and for a while it look like it was going great but that changed after six months of them being together." Casey told him and then looked down at the ground to keep his cool about this.

When Kelly saw that he knew this Ryan guy did something really bad to Mac. "What did he do Casey?" Kelly asked trying to keep his cool and not jump all over Casey.

"He started to make her feel like he was all she needed and all that would have her till he had her so convince she started to stay him and not be her bubbly self. She stopped going to school and all she did was stay him and do as he told her to do. It was bad Kelly really bad. She would only talk to Hallie and me on the phone and that was when he wasn't around cause if he knew she was talking to us he would take it out on her and it was not something that we wanted her to go though. We brought her a cell phone that she would hid from Ryan and had the bill come to us. It took Mac a year before she could get up the courage to leave him and when she did she took the first plane out of there and came here where she knew she was safe cause I wouldn't let him near her. Hallie wouldn't either but it really helped to know there was a guy that could beat the hell out of him if he came near her." Casey finished telling him and he could see Casey was already wanting to go and beat the hell out of this Ryan guy.

Casey looked at Kelly and he could see that angry in his face and he knew what he and Hallie thought was true. Kelly was already falling for Mac. Casey just hopped Kelly would not hurt Mac even if it was an accident. Kelly didn't know what to say or do so he just gave Casey a pat on the shoulder and then turned and walk away from the firehouse and not even be there for the day cause he knew his angry would not be able to stay down.

Casey knew what Kelly was thinking and nods his head. "Go Severide and take the day to cool down and think. I will tell the Caption that you needed a day."

Kelly nods his head and walks away without so much as a look back and just gets into his truck and gets the hell out of there and heads to his boxing place to work out this angry he has built up in him.


End file.
